Trace fossils include footprints, trails, burrows, feeding marks, and resting marks. Trace fossils provide information about the organism that is not revealed by body fossils. Trace fossils are formed when an organism makes a mark in mud or sand.
Answer:
D.
Explanation:
I think it may be point because only one section is changing.
Answer:
The answer is: Clonal selection produces memory cells that are long-lived and can recognize the antigen in the future.
Explanation:
